A free radical is aspecies with an unpaired valence electron . State true or false

Answer

**Step-by-Step Solution:**

1. **Definition of Free Radical**: A free radical is defined as a species that has at least one unpaired valence electron. This means that in its outermost electron shell, there is an electron that is not paired with another electron.

2. **Example of a Free Radical**: Consider the methyl radical (CH₃•). In this molecule, carbon (C) has four valence electrons. When it forms bonds with three hydrogen atoms (H), it uses three of its electrons to bond with the hydrogens. However, one electron remains unpaired, making CH₃• a free radical.

3. **Comparison with Lone Pair Electrons**: It is important to distinguish between unpaired electrons and lone pair electrons. A lone pair consists of two paired electrons that do not participate in bonding. For instance, in a water molecule (H₂O), the oxygen atom has two lone pairs of electrons. These lone pairs are not considered unpaired electrons.

4. **Conclusion**: Since a free radical is characterized by having an unpaired valence electron, the statement "A free radical is a species with an unpaired valence electron" is true.

**Final Answer**: True.

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